Liquid crystal display devices have been applied to, for example, watches, calculators, a variety of measuring equipment, panels used in automobiles, word processors, electronic notebooks, printers, computers, television sets, clocks, and advertising boards. Representative examples of types of liquid crystal display devices include a TN (twisted nematic) type, an STN (super twisted nematic) type, and a vertical alignment type and IPS (in-plane switching) type in which a TFT (thin film transistor) is used. Liquid crystal compositions used for such liquid crystal display devices need to satisfy the following requirements: being stable to external elements such as moisture, air, heat, and light; having a liquid crystal phase in a broad temperature range mainly including room temperature as much as possible; having a low viscosity; and enabling a low driving voltage. Liquid crystal compositions contain several to tens of compounds to adjust, for instance, dielectric anisotropy (Δ∈) and/or refractive index anisotropy (Δn) to be values optimum to individual display devices.
A liquid crystal composition having a negative Δ∈ is used in vertical alignment (VA)-type displays, and a liquid crystal composition having a positive Δ∈ is used in horizontal alignment-type displays such as a TN type, an STN type, and an IPS (in-plane switching) type. Another type of driving has been reported, in which molecules of a liquid crystal composition having a positive Δ∈ are vertically aligned in a state in which voltage is not applied, and then a horizontal electric field is applied for performing display. A demand for a liquid crystal composition having a positive Δ∈ has therefore further increased. In all types of driving, however, there have been demands for low driving voltage, quick response, and a broad range of operation temperature. In other words, a liquid crystal composition having a positive Δ∈ with a large absolute value, a low viscosity (η), and a high nematic phase-isotropic liquid phase transition temperature (Tni) has been demanded. In view of Δn×d that is a product of Δn and a cell gap (d), the Δn of a liquid crystal composition needs to be adjusted to be in a range suitable for the cell gap. In addition, quick response is important in liquid crystal display devices applied to television sets or other apparatuses, which generates a need for a liquid crystal composition having a small rotational viscosity (γ1).
Liquid crystal compositions which enable quick response have been disclosed; for example, such liquid crystal compositions contain a combination of a liquid crystal compound having a positive Δ∈ and represented by Formula (B) and liquid crystal compounds having a neutral Δ∈ and represented by Formulae (A) and (C). In these liquid crystal compositions, a liquid crystal compound having a positive Δ∈ has a structure of —CF2O—, and a liquid crystal compound having a neutral Δ∈ has an alkenyl group, which is widely known in the field of these liquid crystal compositions (see Patent Literatures 1 to 4).

As liquid crystal display devices have come to be used in a broad range of applications, use and manufacturing thereof have been greatly changed. In order to adapt to such changes, optimization of characteristics other than known basic physical properties has been needed. In particular, a VA type and an IPS type have become popular as liquid crystal display devices utilizing a liquid crystal composition, and display devices having a very large size (e.g., 50 inches or lager) have been practically used. An increase in the size of substrates has changed a technique for putting a liquid crystal composition between substrates, and a one drop fill (ODF) technique has become mainstream in place of a typically employed vacuum injection technique; however, dropping of a liquid crystal composition onto a substrate generates stains of liquid crystal droplets with the result that display quality is degraded, which has been problematic. Furthermore, in a process for manufacturing a liquid crystal display device by an ODF technique, liquid crystal needs to be dropped in an amount optimum for the size of the liquid crystal display device. In the case where the amount of liquid crystal to be dropped largely varies from the optimum level, a predetermined balance between a refractive index and a driving electric field in a liquid crystal display device is disrupted, which causes defective display such as generation of unevenness and defective contrast. In particular, the optimum amount of liquid crystal to be placed is small in small-size liquid crystal display devices widely used in smartphones which have become popular in recent years, and thus it is difficult to even control a variation from the optimum amount to be in a certain range. Hence, in order to maintain a high yield of liquid crystal display devices, for instance, liquid crystal needs to be less affected by a rapid pressure change and impact which are generated in a dropping apparatus during dropping of the liquid crystal and to continuously enable stable dropping thereof for a long time.
In view of these circumstances, a liquid crystal composition used for active-matrix liquid crystal display devices driven by, for example, a TFT device needs to be developed without sacrificing characteristics and performance, such as quick response, needed for liquid crystal display devices while a method for manufacturing liquid crystal display devices is taken into consideration in addition to properties which have been traditionally considered important, such as exhibiting high specific resistance or a high voltage holding ratio and being stable to external elements such as light and heat.